Christians do believe in evolution and dinosaurs, but it's important people discussing the issue classify what they mean by 'evolution' before writing off the argument for 'intelligent design', which is as logically plausible...
Darwin's theory of evolution speculated that one species could / has evolved into another: this is macro evolution. For example, fish into mammals. It's important to state here that this is STILL theory and, to date, has never been proven by ANY scientist / scientific body. Even Darwin concluded - not at the end of his life, but in the closing chapter of "The Origin of the Species", that there was room for belief in a 'Creator'.
Evolution on a micro level is where one species evolves within a species - this is absolutely proven, and happens every day. For example, today we are several inches taller on average than our Grandparents, and this is something that took place within a generation. Micro evolution is proven.
The problem is that we have all been taught - whether at school, by Stephen Fry on QI (!), or by osmosis - that macro evolution is proven. It's an interesting argument, but so full of holes that to accept it without question is like hanging up your brain ...something that Christians are accused of all the time for believing that there is purpose, design and phenomenal intricacies in life!
One of the major flaws with the theory of macro evolution is the contradiction it throws up, specifically in the animal kingdom, of the proven method of procreation 'survival of the fittest'. For a species to evolve into another would take a mutation in form - and not just one, but generation after generation - however, in the animal kingdom 'mutants' are weeded out! It's a pretty ruthless system, but animals only procreate with the 'best' of their species. A mutation would be seen as a weakness and it's highly unlikely therefore that that animal would be able to pass on its mutation to subsequent generations.
Another major flaw is the incredible discovery of DNA. A DNA code is specific to a creature and tells the body what it is, what it's made of - for example, a bird has something in its DNA which allows it to produce feathers, but this doesn't - can't - exist in reptile DNA.
The feather in itself is a mindblowing piece of technology - I for one can't believe that this is random, fluke or self-generated!
Whatever you believe about God / afterlife / spirituality - whatever - to say Christians are halfwits because of a belief in something greater than themselves and human intelligence, but then yourself accept a theory about our existence that is fundamentally flawed... who's the halfwit?? I'd rather have an open mind!
To fully accept and believe in the theory of macro evolution takes as much faith as it does a Christian to believe in God :)